They were then joined by an Israeli Merkava tank. Equipped with a powerful 120 mm cannon, this tank was of no use at the time, except as a refuge thanks to its armored plating. Dozens of participants took cover behind it, along with some of the police. Bullets rattled. The assailants were there.

The article seems to say that the tank was there before Hamas. So maybe the ravers were caught in the crossfire.